SEDDS systems

Araya H, Tomita M, Hayashi M (2006) The novel formulation design of self-emulsifying drug delivery systems (SEDDS) type O/W microemulsion III The permeation mechanism of a poorly water soluble drug entrapped O/W microemulsion in rat isolated intestinal membrane by the Ussing chamber method. Drug Metab Pharmacokinet 21 45-53. 

Self-emulsifying drug delivery systems (SEDDS) are anhydrous solutions of the drug in oil containing surfactant and cosurfactant, which spontaneously emulsify when added to an excess of water. 

Indeed, recently SEDDS themselves have been delivered as liquids absorbed onto powders such as colloidal silicon dioxide or microcrystalline cellulose (Nazzal et al., 2002). Selection of the absorbent was obviously critical to the performance of the system but, as an aside, it seems that this approach negates the rapid release properties of a SEDDS. It will be interesting to follow the future of this technology. 

To some degree the selection of components for a SEDDS will be determined by the properties of the drug itself but, ideally, the final system concentrate prior to dilution should be... 

Kommuru, T.R., Gurley, B., Khan, M.A., Reddy, I.K. (2001). Self-emulsifying drug delivery systems (SEDDS) of coenzyme Q10 formulation development and bioavailability assessment. International Journal of Pharmaceutics, 212, 233-246. 

Patil, P, J. Joshi, and P. Paradkar. 2004. Effect of formulation variables on preparation and evaluation of gelled self-emulsifying drug delivery systems (SEDDS) of ketoprotetfPS Pharm Sci Te[Pg.527]

Self-Emulsifying Systems Emulsion systems have the disadvantage of being physically unstable, and over time a separation between the oil and water phases of the emulsion will occur. The use of conventional emulsions is also less attractive due to poor precision of the taken dose and the relatively large volume that has to be administered. To overcome these limitations, self-emulsifying drug delivery systems (SEDDS) have been developed. The... 

Currently, most mature dissolution controlled release systems/ technologies are applicable for water-soluble and low-water-solubility compounds (with low doses). For very poorly water-soluble compounds, dissolution controlled release systems/technologies may not be applicable because these compounds have intrinsically slow dissolution/release rates. Recently, several new technologies such as solid dispersions and self-emulsifying drug delivery systems (SEDDS) have been developed to deliver poorly water-soluble compounds at reasonable doses through enhancement of dissolution rate. These technologies have created new potentials for controlled release of poorly water-soluble compounds, often... 

N. H. Shah, M. T. Carvajal, C. I. Patel, M. H. Infeld, and A. W. Malick, Self-emulsifying drug delivery systems (SEDDS) with polyglycolyzed glycerides for improving in vitro dissolution and oral absorption of lipophilic drugs, Int. J. Pharmaceut. 106 15-23 (1994). 

Gursoy, R. N., and Benita, S. (2004), Self-emulsifying drug delivery systems (SEDDS) for improved oral delivery of lipophilic drugs, Biomed. Pharmacother. Dossier Drug Deliv. Drug Efficacy, 58,173-182. 

There are many different polyglycolyzed glycerides and they are generally used to formulate water-insoluble drugs in lipid based formulations such as self-emulsifying drug delivery systems (SEDDS) in order to improve oral... 

Microemulsions are thermodynamically stable isotropically clear dispersions composed of a polar solvent, oil, and a surfactant(s). Labrafil and Gelucire 44/14 are all-in-one self-emulsifying surfactants which are in many oral products throughout the world. Microemulsions have much potential for drug-delivery since very hydrophobic molecules can be solubilized and formulated for oral administration (Tenjarla, 1999). All of the commercial products are actually nonaqueous microemulsions, also known as microemulsion preconcentrates or self-emulsifying drug delivery systems (SEDDS), since the polar solvent is not water. Upon contact with aqueous media, such as gastrointestinal fluids, a SEDDS formulation spontaneously forms a fine dispersion or aqueous microemulsion. 

SEDDS.self-emulsrfying drug delivery system... 

Table 2 Bioavailability Parameters Obtained in Male Beagle Dogs (mean SD, n = 3) After Oral Administration of 50 mg of Hf Base Formulated as Either a Long chain Self-microemulsifying Formulation (SMEDDS) or a Medium-chain Self-emulsifying (SEDDS), or Self-microemulsifying Drug Delivery System (SMEDDS)...

This principle of anhydrous concentrates was named SMEDDS , self micro-emulsifying dmg delivery systems. Such formulations lack the aqueous phase. On dilution, a SMEDDS spontaneously converts to an optically clear, thermodynamically stable microemulsion, which contains the dmg in molecular dispersion. The same principle of a water-free concentrate which leads to a macro -emulsion is called SEDDS, a self-emulsifying dmg delivery system. A recent review on self-dispersing lipid based systems was... 

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